There are ways to build a 396, but there aren't as many options as a 454. There are a few tricks to them. Piston options are narrow these days, KB only makes 1 type. TRW is another that I think makes a couple different ones. None of them make more than 9.5 to 1 compression with new style open chamber heads, and that's with a huge 45cc dome. So if you want to build a stout 396, you are stuck with old 60's closed chamber type heads.

Find out which 396 this is and I could help you out more. Check the numbers on the heads, and post them.

Pat is right, if you want the best bang for your buck, a 454 would be a better idea. A lot of people like 396's though because they rev like a small block. 427's are nice too.